package com.example.base.utils;

import javax.servlet.http.HttpServletRequest;
import java.net.*;
import java.util.Enumeration;

/**
 * @author X.I.O
 * @title: IPUtils
 * @projectName springboot
 * @description: TODO
 * @date 2022/1/4 15:30
 */
public class IPUtils {

    private static String IP=null;

    static {
        IP=getRealIP();
    }

    public static String getIPv4IP(){
        if(IP==null){
            IP=getRealIP();
        }
        return IP;
    }

    //获取电脑的ipv4地址
    private static String getRealIP() {
        try {
            Enumeration<NetworkInterface> allNetInterfaces = NetworkInterface
                    .getNetworkInterfaces();
            while (allNetInterfaces.hasMoreElements()) {
                NetworkInterface netInterface = (NetworkInterface) allNetInterfaces
                        .nextElement();

                // 去除回环接口，子接口，未运行和接口
                if (netInterface.isLoopback() || netInterface.isVirtual()
                        || !netInterface.isUp()) {
                    continue;
                }

                if (!netInterface.getDisplayName().contains("Intel")
                        && !netInterface.getDisplayName().contains("Realtek")) {
                    continue;
                }
                Enumeration<InetAddress> addresses = netInterface
                        .getInetAddresses();
                //System.out.println(netInterface.getDisplayName());
                while (addresses.hasMoreElements()) {
                    InetAddress ip = addresses.nextElement();
                    if (ip != null) {
                        // ipv4
                        if (ip instanceof Inet4Address) {
                            System.out.println("ipv4 =" + ip.getHostAddress());
                            return ip.getHostAddress();
                        }
                    }
                }
                break;
            }
        } catch (SocketException e) {
            System.err.println("Error when getting host ip address"
                    + e.getMessage());
        }
        return null;
    }


    public static String getIpAddr(HttpServletRequest request) {
        String ipAddress = null;
        try {
            ipAddress = request.getHeader("x-forwarded-for");
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("WL-Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getRemoteAddr();
                if (ipAddress.equals("127.0.0.1")) {
                    // 根据网卡取本机配置的IP
                    InetAddress inet = null;
                    try {
                        inet = InetAddress.getLocalHost();
                    } catch (UnknownHostException e) {
                        e.printStackTrace();
                    }
                    ipAddress = inet.getHostAddress();
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            if (ipAddress != null && ipAddress.length() > 15) { // "***.***.***.***".length()
                // = 15
                if (ipAddress.indexOf(",") > 0) {
                    ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
                }
            }
        } catch (Exception e) {
            ipAddress="";
        }
        // ipAddress = this.getRequest().getRemoteAddr();
        return ipAddress;
    }
}
